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Full-Text Articles in Physical Sciences and Mathematics
Process-Based Evaluation Of Stochastic Perturbed Parameterization Tendencies On Ensemble Forecasts Of Heavy Rainfall Events, Kevin Michael Lupo
Process-Based Evaluation Of Stochastic Perturbed Parameterization Tendencies On Ensemble Forecasts Of Heavy Rainfall Events, Kevin Michael Lupo
Legacy Theses & Dissertations (2009 - 2024)
Stochastic model error schemes, such as the stochastic perturbed parameterization tendencies (SPPT) and independent SPPT (iSPPT) schemes, have become an increasingly utilized method to represent model error associated with uncertain subgrid-scale processes in ensemble prediction systems (EPSs). While much of the current literature focuses on how stochastic methods influence ensemble skill, relatively less attention is given to the processes by which these schemes lead to forecast variability. In this vein, this dissertation examines the physical processes by which the application of SPPT and iSPPT to the microphysics, planetary boundary layer (PBL), and radiation parameterization schemes yields rainfall forecast variability. These …
Factors Influencing Rainfall Over The Congo, Ajay Raghavendra
Factors Influencing Rainfall Over The Congo, Ajay Raghavendra
Legacy Theses & Dissertations (2009 - 2024)
The hydrological cycle over tropical rainforests includes some of the most intense thunderstorms and rainfall totals. The energy associated with this convective activity plays an important role in the Earth’s weather and climate system. Therefore, the interannual variability, trends, and future climate projections of the hydrological cycle over tropical rainforests are important topics for research. The Congo rainforest situated over equatorial Africa is the second largest rainforest in the world, and recent studies have documented a >30-year large-scale and long-term drying trend over the Congo since the late-1970s. However, unlike the Amazon rainforest in South America, the Congo rainforest is …
Dynamical Downscaling Of Near-Term Climate Variability And Change For The Main Hawaiian Islands Using Wrf, Katrina Marie Fandrich
Dynamical Downscaling Of Near-Term Climate Variability And Change For The Main Hawaiian Islands Using Wrf, Katrina Marie Fandrich
Legacy Theses & Dissertations (2009 - 2024)
As climate models continue to improve, the demand from resource managers and decision-makers for more accurate climate projections is increasing. However, natural climate variability poses a limit to the confidence in regional climate change projections, particularly for the mid-21st century. The unique geographic location of the Hawaiian Islands and its regional climate provide a challenging opportunity for climate modelers. The goal of this project is to examine both the Pacific Decadal Oscillation (PDO) and anthropogenic climate change for their impacts on near-term rainfall and temperature projections for the Hawaiian Islands. Of primary interest are the questions 1) is there a …
A Multiscale Analysis Of The Rainband And Cellular Structure In Hurricanes Harvey And Irma (2017) Using The Ncar Ensemble, Dylan Card
Legacy Theses & Dissertations (2009 - 2024)
Tropical cyclones pose a significant threat to life and property, and exhibit many severe weather hazards as they make landfall, such as storm surge, strong winds, flooding rains, and tornadoes. Tropical cyclone rainbands are associated with nearly all of these hazards, which can extend hundreds of kilometers inland. Thus, understanding tropical cyclone rainband structure, and the individual convective cells of which rainbands are composed, is important to mitigating risk. Several previous studies have documented the overall structure of tropical cyclone rainbands, including the cells of which they are comprised and the environments in which they are embedded. These studies have …
Precipitation Characteristics And Their Dependence On Data Resolution And Model Physics, Di Chen
Precipitation Characteristics And Their Dependence On Data Resolution And Model Physics, Di Chen
Legacy Theses & Dissertations (2009 - 2024)
To fully characterize precipitation, one often needs not only the accumulative amount (A), but also its frequency (F), intensity (I) and duration (D). These characteristics have large impacts on Earth’s hydrologic cycle. Aiming for a comprehensive understanding, this dissertation investigates precipitation characteristics and their dependence on data resolution and model physics using observational datasets and comprehensive global climate models (GCMs).
Changes In Extreme Precipitation In The Northeast United States : 1979-2014, Macy Howarth
Changes In Extreme Precipitation In The Northeast United States : 1979-2014, Macy Howarth
Legacy Theses & Dissertations (2009 - 2024)
Extreme precipitation can have significant adverse impacts on infrastructure and property, human health, and local economies. This thesis examines recent changes in extreme precipitation in the Northeast United States, which here includes the states of Maine, New Hampshire, Vermont, New York, Massachusetts, Connecticut, Rhode Island, Pennsylvania, and New Jersey. Daily station data from 58 stations missing less than 5% of days for the years 1979–2014 from the United States Historical Climatology Network was used to analyze both total and extreme precipitation, with the latter defined as the top 1% of days with precipitation.
Understanding The Relationship Between Winter Hawaii Precipitation And North Pacific Climate Variability For Past And Present Climate Conditions, Siyu Li
Legacy Theses & Dissertations (2009 - 2024)
Kona lows (KLs) are a type of seasonal cut-off cyclones in the North Pacific around the Hawaiian Islands during the cold season month (Oct.-Apr.). KLs are important for the annual rainfall budget of the Hawaiian Islands. This study investigates what controls the winter precipitation variability over the Hawaiian Islands in the present-day climate and within a long-term paleoclimate simulation. ERA-interim data from 1979-2014 are used for the present-day analysis of the large-scale circulation. The potential vorticity is used as a measure of extratropical synoptic activity. The Hawaii Rainfall Index is from the Rainfall Atlas of Hawaii (seasonal means, 1920-2012). For …
Ensemble Variability In Rainfall Forecasts Of Hurricane Irene (2011), Molly Becker Smith
Ensemble Variability In Rainfall Forecasts Of Hurricane Irene (2011), Molly Becker Smith
Legacy Theses & Dissertations (2009 - 2024)
As tropical cyclones (TCs) move into the midlatitudes, they are often associated with extensive heavy precipitation. This precipitation can lead to widespread flooding events, such as occurred with Hurricane Irene (2011) over the northeastern United States. Despite the high-impact nature of these events, there are relatively few studies that explore the sensitivity of precipitation forecasts to model initial conditions, beyond focusing on the variability in forecast TC track.
Rossby Wave Breaking And Widespread Extreme Precipitation Events In The Central And Eastern U.S, Benjamin John Moore
Rossby Wave Breaking And Widespread Extreme Precipitation Events In The Central And Eastern U.S, Benjamin John Moore
Legacy Theses & Dissertations (2009 - 2024)
This dissertation examines climatological and dynamical linkages between widespread extreme precipitation events (EPEs) in the central and eastern U.S. and Rossby wave breaking (RWB), and assesses forecast skill for EPEs occurring in conjunction with RWB. The analysis primarily focuses on linkages of EPEs to LC1 (anticyclonic) and LC2 (cyclonic) RWB.
Chilean Coastal Orographic Precipitation Experiment : A Tale Of Two Rain Regimes, Adam Massmann
Chilean Coastal Orographic Precipitation Experiment : A Tale Of Two Rain Regimes, Adam Massmann
Legacy Theses & Dissertations (2009 - 2024)
The Chilean Coastal Orographic Precipitation Experiment Pilot Project (CCOPE-2015) was an exploratory field campaign to better understand the mechanisms of orographic precipitation enhancement in the Nahuelbuta Mountains of Southern Chile (38 deg. S.). Observations collected include: (1) surface rainfall from a network of 10 data logging rain gauges, (2) vertical precipitation profiles from a pair of K-band Micro Rain Radars, (3) rain drop size distributions from an optical disdrometer, (4) upstream wind and thermodynamic profiles from radiosonde launches, and (5) aerosol number concentration and size distribution measurements from a condensation particle counter and an ultra-high sensitivity aerosol spectrometer.
Extreme Hydrometeorological Events In The Peruvian Central Andes During Austral Summer And Their Relationship With The Large-Scale Circulation, Juan Carlos Sulca
Extreme Hydrometeorological Events In The Peruvian Central Andes During Austral Summer And Their Relationship With The Large-Scale Circulation, Juan Carlos Sulca
Legacy Theses & Dissertations (2009 - 2024)
In this Master's dissertation, atmospheric circulation patterns associated with extreme hydrometeorological events in the Mantaro Basin, Peruvian Central Andes, and their teleconnections during the austral summer (December-January-February-March) are addressed. Extreme rainfall events in the Mantaro basin are related to variations of the large-scale circulation as indicated by the changing strength of the Bolivian High-Nordeste Low (BH-NL) system. Dry (wet) spells are associated with a weakening (strengthening) of the BH-NL system and reduced (enhanced) influx of moist air from the lowlands to the east due to strengthened westerly (easterly) wind anomalies at mid- and upper-tropospheric levels. At the same time extreme …
Rainfall And Streamflow Variability In Ghana, Michael Mawutor Tanu
Rainfall And Streamflow Variability In Ghana, Michael Mawutor Tanu
Legacy Theses & Dissertations (2009 - 2024)
The objective of this research is to investigate the variability of rainfall and streamflow over Ghana. Analyses of rainfall shows larger daily variability and maxima amounts in the southern coastal belt than in either the middle or northern parts of the country. The high variability in rainfall at the coast is associated with sea surface temperatures (SSTs) changes over the Guinea coast. This is related to the evolution of the cold tongue over the Atlantic during the rainfall season. The results indicate that the extreme rainfall events occur as single events, but there are occasions when they occur sequentially, and …